JP2019512401A - Tool holder with conical internal thread and rotary cutting tool with interchangeable cutting head with parallel external thread and said tool holder - Google Patents

Abstract

The rotary cutting tool (20) comprises a replaceable cutting head (22) and a tool holder (24). The replaceable cutting head (22) comprises a forward cutting (26) and a rear attachment (28). The mounting portion (28) includes a male coupling member (38) that includes parallel external threads (42). The tool holder (24) comprises a female coupling member (68) which comprises a conical internal thread (72). When the rotary cutting tool (20) is in the locked position, the external thread (42) threadably engages with the internal thread (72). [Selected figure] Figure 1

Description

  The subject matter of the present application relates to a rotary cutting tool of the type in which a replaceable cutting head having a male coupling member is removably held in a female coupling member of a tool holder by means of a threaded coupling mechanism.

  The rotary cutting tool can be provided with a threaded coupling mechanism or “tool joint” for holding the replaceable cutting head fixedly in the tool holder.

  The replaceable cutting head can include a male coupling member and the tool holder can include a female coupling member. The male coupling member can include an external thread. The female coupling member can include an internal thread corresponding to the external thread of the male coupling member.

  In some such rotary cutting tools, the internal and external threads are both parallel threads. An example of such a rotating cutting tool is disclosed, for example, in US Pat. No. 6,485,220.

  In other such rotary cutting tools, the internal and external threads are both taper threads. Examples of such rotary cutting tools are disclosed, for example, in U.S. Patent Nos. 7,611,311 and 7,713,004.

According to a first aspect of the subject matter of the present application, a rotary cutting tool having a longitudinal axis and extending from a forward direction to a backward direction, comprising:
A tool holder having a holder longitudinal axis, comprising a female coupling member having an internal thread extending rearward from the holder front surface, the holder front surface extending transverse to the holder longitudinal axis A tool holder,
A replaceable cutting head having a head longitudinal axis, wherein
A front portion forming a cutting portion,
A rear portion forming an attachment portion, the attachment portion including a male coupling member having an external thread and projecting rearwardly from the head base surface, the head base surface being transverse to the head longitudinal axis A replaceable cutting head including a rear portion extending and defining a boundary between the cutting portion and the mounting portion;
The male screw of the male coupling member is a parallel screw,
The female screw of the female coupling member is a conical screw,
The rotating cutting tool
A release position in which the male coupling member is located outside the female coupling member and the internal and external threads are not threadingly engaged with one another
A rotary cutting tool is provided, adjustable between a locking position, in which a male coupling member is removably held in a female coupling member and an internal thread and an external thread are threadably engaged with one another. .

According to another aspect of the subject matter of the present application, it includes a female coupling member having a holder longitudinal axis extending rearward from a front direction and having an internal thread extending rearward from a holder front surface, the holder front side A tool holder, the faces of which extend transversely to the holder longitudinal axis,
The female screw of the female coupling member is a conical screw,
An internal thread helically extending about an internal thread axis and comprising an internal thread comprising a front inner flank surface and a rear inner flank surface and an inner upper surface extending therebetween;
The front inner flank surface and the rear inner flank surface generally face in opposite axial directions and delimit a helical female thread including an inner bottom surface;
At least one of an internal thread and an internal thread groove extends around a respective cone having a conical angle,
A tool holder is provided, wherein the cone angle is in the range of 0.02 ° ≦ γ ≦ 1.6 °.

According to yet another aspect of the subject matter of the present application, a rotary cutting tool having a longitudinal axis and extending from a forward direction to a backward direction, comprising:
A replaceable cutting head having a head longitudinal axis, wherein
A front portion forming a cutting portion,
A rear portion forming an attachment portion, the attachment portion including a male coupling member having an external thread and projecting rearwardly from the head base surface, the head base surface being transverse to the head longitudinal axis A replaceable cutting head including a rear portion extending and defining a boundary between the cutting portion and the mounting portion;
The male screw of the male coupling member is a parallel screw,
The rotating cutting tool
A release position in which the male coupling member is located outside the female coupling member and the internal and external threads are not threadingly engaged with one another
A rotary cutting tool is provided, adjustable between a locking position, in which a male coupling member is removably held in a female coupling member and an internal thread and an external thread are threadably engaged with one another. .

  What is described above is an outline, and that the features described below may be applicable in any combination to the subject matter of the present application, eg any one of the following features being rotary cut It is understood that it may be applicable to tools and / or tool holders.

The internal thread includes an internal thread helically extending about an internal thread axis and including a front inner flank surface and a back inner flank surface and an inner upper surface extending therebetween, the front inner flank surface And aft inner flanks generally face in opposite axial directions and delimit a helical female thread including an inner bottom surface;
In the release position
At least one of the internal thread and the internal thread groove extends around a respective cone having a conical angle,
The cone angle may be in the range of 0.02 ° ≦ γ ≦ 1.6 °.

  The cone angle can be exactly equal to 0.8 °.

  Only internally threaded grooves can extend around the respective cones.

  In a cross-sectional view in an axial plane including the internal thread axis, the inner upper surface forms a plurality of internal thread crests that may be parallel to and colinear with the internal thread axis, and the inner bottom surface is parallel to the internal thread axis And forming a plurality of female thread troughs according to a pattern which is in the rear direction and in which the distance from the female thread shaft decreases.

  The front inner flank surface and the rear inner flank surface are offset from the internal thread axis by a distance which can be reduced as the internal thread helically extends around the internal thread axis in the rearward direction.

The male screw includes male threads helically extending about an male screw axis and including a front outer flank surface and a rear outer flank surface and an outer upper surface extending therebetween, the front outer flank surface and the rear The outer flanks generally face in opposite axial directions and delimit a helical external thread comprising an outer base surface;
The front outer flank surface and the front inner flank surface face in the front direction, the rear outer flank surface and the rear inner flank surface face in the rear direction, and in the locked position,
The aft inner flanks can abut the aft outer flanks.

  In the locked position, the front inner flank may be spaced from the rear outer flank. The inner top surface may be spaced from the outer bottom surface. The inner bottom surface may be spaced apart from the outer top surface.

  In a cross-sectional view in an axial plane including an external thread axis, the outer upper surface forms a plurality of external thread crests that may be parallel to and colinear with the external thread axis, and the outer bottom surface is parallel to the external thread axis And form a plurality of externally threaded valley roots that are co-linear with one another.

  In a cross-sectional view in an axial plane that includes the head longitudinal axis, the external thread defines an external thread shape that may be trapezoidal.

  In a cross-sectional view in an axial plane including the holder longitudinal axis, the internal thread defines an internal thread shape that may be trapezoidal.

The male screw includes a male thread helically extending about an male screw axis and including a front outer flank surface and a rear outer flank surface and an outer upper surface extending therebetween
The front outer flank surface and the rear outer flank surface generally face in opposite axial directions and delimit a helical external thread groove including an outer bottom surface;
The front outer flank surface and the front inner flank surface face in the forward direction,
The aft outer flanks and the aft inner flanks face rearwardly,
In the lock position
The aft inner flanks can abut the aft outer flanks,
The front inner flanks can be spaced from the rear outer flanks,
The inner top surface can be spaced from the outer bottom surface,
The inner bottom surface can be spaced apart from the outer top surface,
The frictional engagement between the external thread and the internal thread can be increased in the direction from the frontmost turn of the external thread to the rearmost turn of the external thread.

  For a better understanding of the present application, and to show how the present application may be practically implemented, reference is now made to the accompanying drawings.

It is a perspective view longitudinal cross-sectional view of a rotary cutting tool. It is a disassembled exploded perspective longitudinal cross-sectional view of the rotary cutting tool shown in FIG. Figure 3 is a side view of the replaceable cutting head shown in Figures 1 and 2; It is a detail of FIG. It is a perspective view of the tool holder shown in FIG.1 and FIG.2. It is a longitudinal cross-sectional view of the female type | mold coupling member shown in FIG. FIG. 2 is a detail of the longitudinal cross-sectional view of the rotary cutting tool shown in FIG. 1 when the rotary cutting tool is in the locked position; FIG. 10 is a schematic view of a female internal thread shape of a conical internal thread, with the internal female thread shape of the parallel internal thread and the external thread shape of the parallel external thread superimposed on each other. FIG. 10 is four views showing the distribution of contact forces on parallel external threads that are respectively threadingly engaged with parallel internal threads and conical internal threads when the rotary cutting tool is assembled and operating.

  It will be appreciated that, for the sake of simplicity and clarity, the elements shown in the figures are not necessarily drawn to scale. For example, for the sake of clarity, the dimensions of some of the elements may be exaggerated relative to other elements, or some physical components may be in one functional block or element. It may be included. Where considered appropriate, reference numerals may be repeated among the figures to indicate corresponding or analogous elements.

  The following description describes various aspects of the subject matter of the present application. For the purpose of illustration, specific configurations and details are set forth in sufficient detail to provide a thorough understanding of the subject matter of the present application. However, it will also be apparent to one skilled in the art that the subject matter of the present application may be practiced without the specific configuration and details presented herein.

  First, it should be noted in FIGS. 1 and 2 which show a rotary cutting tool 20 of the type used in milling operations, in particular high-speed face milling, according to an embodiment of the subject matter of the present application. The rotary cutting tool 20 has a tool longitudinal axis L, about which the tool rotates in a rotational direction R.

The rotary cutting tool 20 comprises a replaceable cutting head 22 having a head longitudinal axis A around which the replaceable cutting head 22 rotates in a rotational direction R. The head longitudinal axis A extends from the front direction D _F to the back direction D _R. The replaceable cutting head 22 can typically be made of cemented carbide.

  The rotary cutting tool 20 also includes a tool holder 24 having a holder longitudinal axis C. The tool holder 24 can typically be made of steel. A replaceable cutting head 22 can be removably retained within the tool holder 24 using a threaded coupling mechanism. Such threaded coupling mechanisms may be advantageous for other types of rotary cutting operations, such as, for example, reaming or drilling.

  The use of the terms "forward" and "backward" throughout the specification and claims, as illustrated in FIG. 1, relates to the relative position of the replaceable cutting head 22 to the tool holder 24 of the assembled rotating cutting tool 20. It should be understood to refer to position. The terms "forward" and "rearward" also refer to the holder length towards left and right respectively in FIGS. 3 and 4 in the direction of the head longitudinal axis A towards left and right respectively It can also be applied in the direction of the direction axis C.

  Here, please refer to FIG. 3 and FIG. The replaceable cutting head 22 has a front portion forming the cutting portion 26 and a rear portion forming the mounting portion 28. According to some embodiments of the subject matter of the present application, the replaceable cutting head 22 can be formed from a single integrated single piece construction. This is advantageous in that the replaceable cutting head 22 does not have a removable cutting insert (not shown).

  Referring to FIG. 3, the cutting portion 26 includes at least one outer peripheral cutting edge 30. In this non-limiting example shown in the drawings, there can be exactly two peripheral cutting edges. Each outer peripheral cutting edge 30 is formed at the intersection of the outer peripheral flank 32 and the outer peripheral rake face 34. With respect to the rotational direction R, the outer circumferential flank 32 is disposed rearward of the outer circumferential cutting edge 30 in the rotational direction, and the outer circumferential rake face 34 is disposed forward of the outer circumferential cutting edge 30 in the rotational direction. The metal cutting operation can be performed by the orientation of the outer peripheral cutting edge 30.

  According to some embodiments of the subject matter of the present application, the cutting portion 26 may include at least one groove 36 for discharging chips (not shown) generated during the cutting operation. One groove 36 is associated with each peripheral cutting edge 30. The replaceable cutting head 22 can include one or more bottom blades 30 b at the end face 37 of the cutting portion 26. In this non-limiting example shown in the drawings, the replaceable cutting head 22 can include exactly two bottom blades 30b. Each of the two bottom blades 30b can have an associated side blade 30a.

  Referring now to FIGS. 3 and 4, the mounting portion 28 includes a male coupling member 38 projecting rearward from the head base surface 40. The head base surface 40 extends transverse to the head longitudinal axis A and defines a boundary between the cutting portion 26 and the mounting portion 28. That is, the cutting portion 26 is formed in the front of the head base surface 40, and the attachment portion 28 is formed in the rear of the head base surface 40. According to some embodiments of the subject matter of the present application, male coupling member 38 may be rigid. The head base 40 may be perpendicular to the head longitudinal axis A. As described below, the head base 40 is intended to abut the corresponding surface of the tool holder 24 when the rotary cutting tool 20 is in the locked position.

Male coupling member 38 includes an external thread 42. Referring to FIG. 4, the male screw 42 includes a male thread 44 helically extending around the male screw axis B. The male screw shaft B coincides with the head longitudinal axis A. Thus, the externally threaded portion 42 and the replaceable cutting head 22 are coaxial. The external thread 44 includes a front outer flank 46 and a rear outer flank 48 and an outer upper surface 50 extending therebetween. The forward outer flank 46 and the rearward outer flank 48 face in opposite axial directions D _F , D _R , the forward outer flank 46 faces in the forward direction D _F and the aft outer flank 48 in the reverse direction D _R Facing the The front outer flank 46 and the rear outer flank 48 delimit the externally threaded groove 52. The externally threaded groove 52 spirally extends about the externally threaded axis B and includes an outer bottom surface 54.

  In the cross-sectional view in the axial plane (i.e., the plane including the male screw axis B), the outer upper surface 50 forms a plurality of male thread crests 56 and the outer bottom surface 54 forms a plurality of male thread valley bottoms 58. According to some embodiments of the subject matter of the present application, the plurality of external thread crests 56 may be parallel to the external thread axis B and colinear with one another. The plurality of externally threaded valleys 58 may be parallel to the externally threaded axis B and colinear with one another.

  In a cross-sectional view in an axial plane including male screw axis B, the front outer flank 46 and the rear outer flank 48 can be inclined at an outer flank angle α with respect to a radial plane perpendicular to the male screw axis B . Preferably, the outer flank angle α may be about 17 °. The external thread 42 defines an external thread shape 60 which may be trapezoidal. The outer top surface 50 and the outer bottom surface 54 may transition smoothly to the front outer flank 46 and the rear outer flank 48, respectively, to define a radius. Alternatively, male thread shape 60 may be triangular.

The outer top surface 50 and the outer bottom surface 54 can form an edge. The plurality of external thread crests 56 define the outer diameter of the external thread 42, and the plurality of external thread valleys 58 define the diameter of the valley of the external thread 42. The value obtained by subtracting the diameter of the valley from the outer diameter and dividing by 2 is equal to the height H _E of the external thread of the external thread 42. Male thread height H _E can be constant. According to some embodiments of the subject matter of the present application, the external thread 42 can have approximately three turns.

  The male screw 42 is a parallel screw. It is to be understood that throughout the present specification and claims that the term "parallel screw" relates to a screw whose threads extend around the cylindrical body and thus the crests are equidistant from the screw axis It is. Similarly, throughout the present specification and claims, the term "taper screw" means that the thread extends around the cone and the surface tapers radially inward towards the screw axis in the backward direction Thus, it should be understood that a screw crest relates to a screw in which the distance from the screw axis is reduced in the rearward direction.

As shown in FIGS. 3 and 4, the male coupling member 38 includes a front support 62. The front support portion 50 is located on the front side of the male screw 42. Front support portion 62 includes a front head abutment surface 64 is tapered radially inwardly toward the head longitudinal axis A in the rearward direction D _R. That is, the front head abutment surface 64 has a conical shape facing radially outward. It should be noted that the front head abutment surface 64 is intended to abut the corresponding surface of the tool holder 24 when the rotary cutting tool 20 is in the locked position, as described below.

  The use of the terms "radially inward / inwardly" and "radially outward / outwardly" throughout the specification and claims refer to the longitudinal head A and / or head longitudinal axis in FIGS. 3 and 4 and FIG. It should be understood to refer to the relative position towards and away from the respective axis in a direction perpendicular to the holder longitudinal axis C.

Referring now to FIGS. 5 and 6, the tool holder 24 has a holder longitudinal axis C extending in the rear direction D _R from the front direction D _F. The tool holder 24 includes a female coupling member 68 extending rearward from the holder front surface 70. The holder front surface 70 extends transverse to the holder longitudinal axis C. According to some embodiments of the subject matter of the present application, the holder front surface 70 may be perpendicular to the holder longitudinal axis C.

The female coupling member 68 includes an internal thread 72. As shown in the longitudinal cross-sectional view of the female coupling member 68 including the female screw shaft D (ie, FIG. 6), the female screw 72 includes a female screw thread 74 extending helically around the female screw shaft D. The female screw axis D coincides with the holder longitudinal axis C. Thus, the internal thread 72 is coaxial with the tool holder 24. The internal thread 74 includes a front inner flank surface 76 and a rear inner flank surface 78 and an inner top surface 80 extending therebetween. The front inner flank surface 76 and the rear inner flank surface 78 face in opposite axial directions D _F , D _R , the front inner flank surface 76 faces in the forward direction D _F , and the rear inner flank surface 78 in the rear direction D _R Facing the The front inner flank surface 76 and the rear inner flank surface 78 delimit an internally threaded groove 82.

The female screw groove 82 helically extends around the female screw axis D and includes an inner bottom surface 84. In a cross-sectional view in an axial plane (i.e., the plane containing the internal thread axis D), the inner top surface 80 forms a plurality of internal thread crests 88 and the internal bottom surface 84 forms a plurality of internal thread valleys 90. According to some embodiments of the subject matter of the present application, the plurality of internal thread crests 88 may be parallel to the internal thread axis D and colinear with one another. A plurality of female thread root 90 is parallel to the internal thread axis D, the distance from the female thread axis D in the rear direction D _R is obtained in accordance with the pattern to be reduced.

  In a cross-sectional view in the axial plane including the female screw axis (D), the front inner flank 76 and the rear inner flank 78 are inclined at an inner flank angle β with respect to the radial plane perpendicular to the female screw axis Can. Preferably, the inner flank angle β may be about 17 °. The internal thread 72 defines an internal thread shape 86 which may be trapezoidal. Referring now to FIG. 8, the sides of the trapezoid may not be equal in length. The inner top surface 80 and the inner bottom surface 84 may transition smoothly to the front inner flank 76 and the rear inner flank 78, respectively, to define a radius. Alternatively, the internal thread shape 86 may be triangular.

The inner top surface 80 and the inner bottom surface 84 can form an edge. The plurality of internal thread crests 88 define the diameter of the valley of the internal thread 72, and the plurality of internal thread troughs 90 define the external diameter of the internal thread 72. Divided by 2 from the outer diameter minus the diameter of the recess is equal to the internal thread height H _I of the internal thread 72. The internal thread height H _I , if constant, increases in the backward direction D _R depending on which of the internal thread 74 and the internal thread groove 82 extends around the respective cone K or It may be reduced. In this non-limiting example shown in the drawings, the internal thread height H _I reduces backward. According to some embodiments of the subject matter of the present application, the internal thread 72 can have approximately three turns. The female screw 72 is a conical screw. Throughout the specification and claims the term "conical screw" means that at least one of the threads and grooves extends around the respective cone and the surface has a radius towards the screw axis in the backward direction It is to be understood that the thread is tapered inwardly so that at least one of the thread crest and the thread root is at a reduced distance from the screw axis in the rearward direction. Such a conical screw can be formed by screwing the hollow front end of the cylindrical steel rod with an inner turning insert. The steel rod also moves radially away from the "stationary" cutting insert as it axially rotates and moves to form an internal thread, whereby the screw has a conical shape. The cone and the screw are coaxial. In this non-limiting example shown in FIG. 8, the cone is defined by the point at which the inner bottom surface 84 transitions into the aft inner flank 78.

  According to some embodiments of the subject matter of the present application, at least one of the internal thread 74 and the internal thread groove 82 can extend around the respective cone K with a conical angle γ. The cone angle γ may be in the range of 0.02 ° ≦ γ ≦ 1.6 °. Advantageously, the cone angle γ may be exactly equal to 0.8 °. Only internally threaded grooves 82 can extend around the circumference of the respective cone K. Further, the internal thread 74 can extend around the cylindrical body Y. It is to be further understood that throughout this specification the use of the term "cone angle" refers to the angle formed by the tapered surface of the cone in longitudinal section. It should be noted that the term "longitudinal section" refers to the section in the plane containing the longitudinal axis. With such a longitudinal cross section, the axial plane will include the longitudinal axis.

As shown in FIGS. 5 and 6, the female coupling member 68 includes a front support 92. The front support portion 80 is located on the front side of the female screw 72. Front support portion 92 includes a front holder abutment surface 94 is tapered radially inward toward the holder longitudinal axis C in the backward direction D _R. That is, the front holder abutment surface 94 has a conical shape facing radially inward.

  An assembly of a rotary cutting tool 20 is known, for example, from US Pat. No. 6,485,220 B2, which is incorporated herein by reference in its entirety. It should be noted that the rotary cutting tool 20 is adjustable between the release position and the lock (or assembly) position.

  In the release position, male coupling member 38 is located outside of female coupling member 68.

  In the locked position, male coupling member 38 is removably retained within female coupling member 68. Also, the external thread 42 and the internal thread 72 threadably engage with each other. Referring now to FIG. 7, the front head abutment surface 64 abuts the front holder abutment surface 94. According to some embodiments of the subject matter of the present application, the rearwardly facing head substrate 40 may abut the forwardly facing holder forward surface 70. The aft inner flanks 78 may abut the aft outer flanks 46. The front inner flank surface 76 can be spaced apart from the rear outer flank surface 48. The inner top surface 80 can be spaced from the outer bottom surface 54. The inner bottom surface 84 can be spaced apart from the outer top surface 50.

  Attention is now directed to FIG. 8 which shows a schematic view of the internal thread form 86 of the conical internal thread 72. Using dashed lines, an imaginary internal thread shape 96 of a parallel internal thread and an imaginary external thread shape 98 of a parallel external thread, which threadably engage one another, are superimposed thereon. It should be noted that the cone angle γ of the internal thread 72 forming the internal thread profile 86 is exaggerated to clearly show the internal thread profiles 86, 96 with respect to one another, and thus the distance does not represent a true value.

Each turn of the internal thread shape 86, by the internal thread 72 is conical, a distance to reduce accordance internal thread 72 extends helically around the screw shaft in the rearward direction D _R, deviates from the screw shaft D . Thus, each thread portion of the internal thread shape 86 extends beyond the corresponding thread portion of the virtual internal thread shape 96 (or in other words has a portion "overhanging" such a thread portion ), Whereby each aft inner flank 78 is spaced from the respective imaginary aft inner flank 100 by a flank distance E. Furthermore, Frank distance E, the size in the rear direction D _R increases. In other words, Frank distance E, the size increases in the rearward direction D _R with respect to the winding of the continuous thread. Similarly, each thread portion of female thread shape 86 extends to partially cover (i.e., overlap) the corresponding thread portion of imaginary male thread shape 98, thereby causing each aft inner side The flanks 78 are spaced from the respective imaginary forward outer flank 102 by the same flank distance E. Thus, clearly, when assembled (i.e. engaged in a threaded manner), the frictional engagement between the external thread 42 and the internal thread 72 is in the direction from the foremost turn to the rearmost turn of the external thread 42 Increase.

Here, please refer to FIG. FIG. 9 shows four graphs showing the distribution of contact forces applied to parallel external threads that threadingly engage with parallel internal threads and conical internal threads, respectively, when the rotary cutting tool is assembled and operating. The length of the arrow represents the magnitude of the contact force. When the rotary cutting tool 20 is assembled and in operation, the distribution of contact forces on the conical internal thread and the parallel external thread screwed together (two figures on the right) is a parallel internal thread threadingly engaged with the parallel internal thread. compared to (two figures on the left), it is seen that further located backward D _R. In particular, when the rotary cutting tool 20 having a conical internal thread is assembled, it can be seen that there is almost no contact force in the front region A1 of the parallel external thread. Furthermore, when the rotary cutting tool 20 is in operation, there is a contact force in the rear area A2 of the parallel external thread. The screw type engagement described above improves the stability of the rotary cutting tool 20 against the lateral cutting force.

  Although the subject matter of the present application has been described in some detail, it should be understood that various modifications and changes can be made without departing from the spirit or scope of the invention as set forth in the claims below.

Claims (21)

A rotary cutting tool (20) having a longitudinal axis (L) and extending from a front direction (D _F ) to a back direction (D _R ),
A tool holder (24) having a holder longitudinal axis (C), comprising a female coupling member (68) having an internal thread (72) extending rearward from the holder front surface (70), said holder front surface A tool holder (24), (70) extending transversely to said holder longitudinal axis (C);
A replaceable cutting head (22) having a head longitudinal axis (A),
A front portion forming the cutting portion (26);
A rear portion forming an attachment portion (28), the attachment portion (28) including a male coupling member (38) having an external thread (42) and projecting rearwardly from the head base surface (40) Said head base surface (40) extends transverse to said head longitudinal axis (A) and defines a boundary between said cutting portion (26) and said mounting portion (28) , A rear portion, and a replaceable cutting head (22),
The male screw (42) of the male coupling member (38) is a parallel screw;
Said female screw (72) of said female coupling member (68) is a conical screw;
The rotating cutting tool (20) is
A release position, wherein the male coupling member (38) is located outside the female coupling member (68), and the female screw (42) and the male screw (72) are not in threaded engagement with one another.
A locked position, wherein said male coupling member (38) is removably retained within said female coupling member (68), said female screw (42) and said male screw (72) threadingly engaging one another , Adjustable between, rotary cutting tools (20). The female screw (72) helically extends around the female screw shaft (D), and has a front inner flank surface (76) and a rear inner flank surface (78), and an inner top surface extending between them 80) and including an internal thread (74),
The leading inside flanks (76) and said rear inside flank (78) is generally opposite axial _(D F, _{D R)} facing the helical female screw groove comprising an inner bottom surface (84) (82) Define the boundaries of
At the release position,
At least one of the internal thread (74) and the internal thread groove (82) extends around a respective cone (K) having a cone angle (γ),
The rotary cutting tool (20) according to claim 1, wherein the cone angle (γ) is in the range 0.02 ° γ γ ≦ 1.6 °.   The rotary cutting tool (20) according to claim 2, wherein the cone angle (γ) is exactly equal to 0.8 °.   A rotary cutting tool (20) according to any one of the preceding claims, wherein only the internal thread (82) extends around the respective cone (K).   The rotary cutting tool (20) according to claim 4, wherein the internal thread (74) extends around a cylindrical body (Y). In a cross section in an axial plane including the female screw shaft (D),
The inner upper surface (80) forms a plurality of internal thread crests (88) parallel to and colinear with the internal thread axis (D);
A plurality of internal thread valley bottoms (90) according to a pattern in which the inner bottom surface (84) is parallel to the internal thread axis (D) and the distance from the internal thread axis (D) decreases in the back direction (D _R ). A rotary cutting tool (20) according to any of the claims 2-5, which forms The front inner flank surface (76) and the rear inner flank surface (78) are reduced as the female crest (74) extends helically around the female screw shaft (D) in the rear direction (D _R ) The rotary cutting tool (20) according to any one of claims 2 to 6, which is offset from the internal thread (D) by a distance which The male screw (42) spirally extends around the male screw shaft (B), and has a front outer flank surface (46) and a rear outer flank surface (48), and an outer upper surface extending between them 50) and including an external thread (74),
A helical external thread (52), said front outer flank surface (46) and said rear outer flank surface (48) generally facing in the opposite axial direction (D _F , D _R ) and including an outer bottom surface (54) Define the boundaries of
Said front outer flank surface (46) and said front inner flank surface (76) facing said front direction (D _F );
The aft outer flank surface (48) and the aft inner flank surface (78) face the aft direction (D _R ),
A rotary cutting tool (20) according to any one of claims 2 to 7, wherein in the locked position the aft inner flank (78) abuts the aft outer flank (46). At the lock position:
Said front inner flank surface (76) being spaced from said rear outer flank surface (48);
The inner top surface (80) is spaced from the outer bottom surface (54),
89. The rotary cutting tool (20) according to claim 88, wherein the inner bottom surface (84) is spaced from the outer top surface (50). In a sectional view in an axial plane including the male screw shaft (B),
The outer upper surface (50) forms a plurality of external thread crests (56) parallel to the external thread shaft (B) and colinear with one another;
A rotary cutting tool (20) according to claim 8 or 9, wherein the outer bottom surface (54) forms a plurality of external thread troughs (58) parallel to the external thread axis (B) and colinear with one another. ).   11. A cross-sectional view in an axial plane including the head longitudinal axis (A), wherein the external thread (42) defines an external thread shape (60) that is trapezoidal. Rotary cutting tool (20).   12. A cross-sectional view in an axial plane including the holder longitudinal axis (C), wherein the female screw (72) defines a female screw shape (86) that is trapezoidal. Rotary cutting tool (20). The male screw (42) helically extends around the male screw shaft (B) and has an outer upper surface (50) extending between the outer front flank surface (46) and the rear outer flank surface (48). And an external thread (44),
A helical external thread (52), said front outer flank surface (46) and said rear outer flank surface (48) generally facing in the opposite axial direction (D _F , D _R ) and including an outer bottom surface (54) Define the boundaries of
Said front outer flank surface (46) and said front inner flank surface (76) facing said front direction (D _F );
The aft outer flank surface (48) and the aft inner flank surface (78) face the aft direction (D _R ),
At the lock position:
The aft inner flank surface (78) abuts the aft outer flank surface (46);
Said front inner flank surface (76) being spaced from said rear outer flank surface (48);
The inner top surface (80) is spaced from the outer bottom surface (54),
The inner bottom surface (84) is spaced from the outer top surface (50),
The frictional engagement between the external thread (42) and the internal thread (72) increases in the direction from the foremost winding of the external thread (42) to the rearmost winding of the external thread (42). The rotary cutting tool (20) according to any one of 1 to 12. A female coupling member having a holder longitudinal axis (C) extending from a front direction (D _F ) to a back direction (D _R ) and having an internal thread (72) extending rearward from the holder front surface (70) A tool holder (24) comprising: (68), said holder front surface (70) extending transversely to said holder longitudinal axis (C),
Said female screw (72) of said female coupling member (68) is a conical screw;
The female screw (72) helically extends around the female screw shaft (D), and has a front inner flank surface (76) and a rear inner flank surface (78), and an inner top surface extending between them 80) and including an internal thread (74),
The forward inner flank surface (76) and the aft inner flank surface (78) face generally opposite axial directions (D _F , D _R ) and of a helical internal thread groove (82) including an inner bottom surface (84) Define the boundaries,
At least one of the internal thread (74) and the internal thread groove (82) extends around a respective cone (K) having a cone angle (γ),
Tool holder (24), wherein said cone angle (γ) is in the range of 0.02 ° ≦ γ ≦ 1.6 °.   The tool holder (24) according to claim 14, wherein the cone angle (γ) is exactly equal to 0.8 °.   A tool holder (24) according to claim 14 or 15, wherein only the female thread (82) extends around the respective cone (K).   A tool holder (24) according to any one of claims 14 to 16, wherein the internal thread (72) extends around a cylindrical body (Y). In a cross section in an axial plane including the female screw shaft (D),
The inner upper surface (80) forms a plurality of internal thread crests (88) parallel to and colinear with the internal thread axis (D);
A plurality of internal thread valley bottoms (90) according to a pattern in which the inner bottom surface (84) is parallel to the internal thread axis (D) and the distance from the internal thread axis (D) decreases in the back direction (D _R ). A tool holder (24) according to any of the claims 14-17, which forms   19. A cross-sectional view in an axial plane including the holder longitudinal axis (C), wherein the female thread (72) defines a female thread shape (86) that is trapezoidal. Tool holder (24). The front inner flank surface (76) and the rear inner flank surface (78) are reduced as the female crest (74) extends helically around the female screw shaft (D) in the rear direction (D _R ) Tool holder (24) according to any of the claims 14-19, which is offset from the internal thread (D) by a distance which A rotary cutting tool (20) having a longitudinal axis (L) and extending from a front direction (D _F ) to a back direction (D _R ),
21. A tool holder (24) according to any one of claims 14-20.
A replaceable cutting head (22) having a head longitudinal axis (A),
A front portion forming the cutting portion (26);
A rear portion forming an attachment portion (28), the attachment portion (28) including a male coupling member (38) having an external thread (42) and projecting rearwardly from the head base surface (40) Said head base surface (40) extends transverse to said head longitudinal axis (A) and defines a boundary between said cutting portion (26) and said mounting portion (28) , A rear portion, and a replaceable cutting head (22),
The male screw (42) of the male coupling member (38) is a parallel screw;
The rotating cutting tool (20) is
A release position, wherein the male coupling member (38) is located outside the female coupling member (68), and the internal thread and the external thread are not threadingly engaged with each other;
Adjustable between a locking position wherein the male coupling member (38) is removably held within the female coupling member (68) and the internal and external threads are threadingly engaged with one another The rotary cutting tool (20).

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